Coffee grinder feed and control device



WHY W 1951 R L. scHuHMANN v 2,560,26

COFFEE GRINDER FEED AND CONTROL DEVICE Filed Feb. ll, 1946 3 Sheets-Sheet l i fg/j July 17, 1951 R. L. scHUn-IMANN COFFEE GRINDER FEED AND CONTROL DEVICE Fild Feb. 11, 194e 3 Sheets-Sheet 2 My 17, 1951 R. scHUHMANN COFFEE GRINDER FEED AND CONTROL DEVICE Filed Feb. 1l, 1946 3 Sheets-Sheet 5 Patented July 17, 1951 COFFEE GRINDER FEED AND CONTRO DEVICE l Richard L. Schuhmann, Louisville, Ky., assigner to American Duplex Company, Louisville, Ky., a corporation of Kentucky Application February 11, 1946, Serial No. 646,922

4 claims. (c1. ail- 63)l 'I'he present invention relates to grinding mills and, while it has a wide range of prospective application, it is of particular utility in the conversion ofV unmeasured bull: coffee into measured quantities of coffee ground to a desired fineness. 5 livering a measured quantity yof coffee and to The invention is therefore hereinbelow described assure accurate measurement of such quantity. in that connection. yIt is also an object of my invention to provide The invention is addressed to the solution of a av relatively simple mill for converting coffee problem arising from the customary methods of beans into measured quantities of ground coffee,r brewing coffee in hotels,restaurants,and other 10 the 'mill being so arranged that the vcoffee mayv large consuming establishments. When the directly be delivered into the bowl of a vacuuml vendor of hotel-blend coffee grinds the coffee in brewer. his own establishment he must either provide an A further object of my invention is to provide efficient delivery system ,in order to prevent an improved volumetric measuring device with staleing or must employ expensive packaging means for adjusting the setting of said device toA equipment. It is therefore of advantage `to the increase or decrease the volume to be delivered vendor to furnish coffee in bulk or bean form and thereby. i y this advantage is reflected in lower costs to con- Inaccordance with my invention there are pro-` sumers, such costs `being important factors in vided in combination measuring and delivery enterprises of the'c1asses mentioned above. Fur- 20 means of the type adapted to be selectively ad-` ther in many of such establishments both the justed for receiving material to be ground, or for vacuum brewer and the urn, which require difreleasing such materia1,.normally operative grind-` ferent grinds, are used in preparing coffee to be ing means in communication with the measuring. served. Therefore it is desirable that such large and delivery means and adapted to grind material consuming establishments provide their own mills, released therefrom, and means controlled by said thereby to avoid the cost of grinding in the vendmeasuring and delivery means fOr automa'ally; ors'plant as well as to minimize staleing. disabling said grindingmeans when said measur- However, the vacuum .brewer requires a small ing. and delivery means is adjusted for receiving measured amount of extra-fine ground coffee for material. f each gallon of brewed coffee: say,3 ounces of 30 The above and other advantages and capabilground coffee per half-gallon of brewed coffee. ities of my invention will be apparent from a de- I It has heretofore been found impractical to weigh tailed description ofthe accompanying drawings out coffee in such quantities, because of the great in which I have illustrated one form of my in-l waste of coffee, unsanitary and offensive spillage, vention, but the construction therein shown isand excessive time consumed by busy kitchen to be understood as illustrative and not as defin. laborers. Therefore it has become current pracv ing the limits of my invention. 4' tice for the coffee vendor to supply the large .In the accompanying drawings: Fig. lis a side Consumer With measured quantities of coffee elevational View of a complete electrically-powpacked in small containers. Such containers conered coffee grinding plant in accordance with my v siderabl-y increase the cost of coffee to the vendor, 40 invention, partly in section; Fig. 2 is a front ele-v th-e serving establishment and the ultimate convational view of the Fig. 1 embodiment; Fig. 3 is sinner. It is estimated that such cost is three a front elevational View, partly in section, showcents per 3 ounce package. A consideration of ing the measuring and, delivery device included the large volume of coffee consumed in s-uch esin the Fig. 1 embodiment in the "off position tablishments readily shows that the elimination wherein it is adjusted for receiving. material to of this cost factoris a most desirable objective. be measured and ground; Fig. 4 is a similar front It is aprimary object of my invention to proelevational view of the .measuring and delivery vide a coffee grinding mill which is responsive to device, showing it in the on position for deliv- 1 one simple manual `operation to convert unering material to the grinder; Fig. 5 is a top plan ground coffee in bulk form into a measured view of the measuring and delivery device when amount of coffee of a desired neness. Such av set for receiving material; Fig. 6 is a longitudimill avoids the cost of impractical weighing opnal sectional View of the measuring and delivery erations and packaging, permits accurate measdevice, taken on line 6 6 of Fig. 5 and looking urements by unskilled operators, and assures the in the direction of the arrows; Fig. 7 is an axial grinding of the predetermined desired amount sectional view taken on line l-'l of Fig. 6; and

of coffee.

It is also an object of my invention to provide a?. novel grinding mill including a grinder and measuring and delivery device cooperatively so arranged as to minimize the labor involved in de-y Fig. y8 shows the circuit arrangement of the 3 switching means provided for disabling the grinder when the measuring and delivery device is set to be iillcd.

Referring now specifically to Fig. 1, there are shown a hopper II, a novel combination of a measuring and delivery device and a grinder I3; and the upper bowl of a vacuum brewer I4, the bowl being positioned to receive a measured quantity of coffee of a predetermined grind from the grinder. The measuring and delivery deviceand grinder are mounted within a hood I5, securedto a foundation I5. The base IB supports the grinder and measuring andv delivering device as a cantilever, permitting ready placement or bowl I4 to receive ground coiTee.

The overall operation of this grinding. plant' is as follows: Coffee beans are deposited in bulk in hopper I I and introduced into the measuring and delivery device I2, which in turn delivers a measured quantity of the beans to grinder I3. The measured coffee is ground to` a desired fineness and then discharged into brewer I4. The mill is so arranged that one operation of a control lever I1 releases the measured quantity of unground coffee from device I2 to grinder I3 and at the same time starts motor I8, which drives the grinder. Conversely, one manual operation of lever I1 places the measuring device I2 in a condition for being refilled, arrests the delivery ofungroundcoffee to the mill and interrupts the flow of electrical power from an energizing source to the motor, thus disabling the grinder.

In Figs. 5, 6, and '7, there are shown the details of the measuring and delivery devices. Its measuring operation is premised on the cooperation of an outer housing member I9 andV a generally cylindrical rotatable inner barrel member 20. The inner member is concentric with and closely fitted to the outer member and it turns under the control of lever I1. The outer member is formed with axially open ends and with the general contour of a pipe junction. Its lower portion converges downwardly as indicated at 22 into a discharge orice 23. Its upper portion is formed with a flanged mouth 24 for receiving coffee to be ground. On each side of the mouth the interior thickened portions forming the base of this ange are cut out to form sharply defined downwardly sloping shoulders 25 and 26. The barrel 2IIv is formed with an opening 21, defined by longitudinal edges 28 and 29 which register with shoulders 25 and 25 when the measuring and delivery device is in position for filling (as shown in Figs. 5, 6, and '1). In that position the barrel functions as a gate to arrest the ow of unground material to the grinder. When the device is in position for delivery (Fig. 4) the measured coffee drops through openings 21 and 23- to the grinder. In order to assure the de-L livery of a measured amount of coffee, edges 28y and 29 are formed as knife-edge cutters.

Integral with barrel 20 is an end plate 30, having a larger diameter than the barrel, so that its outer margin slidably bears on end 3I of housing I 9 to prevent axial motion of the barrel in one direction. Axial motion of the barrel in the other direction is prevented by an end plate 32 secured to the barrel by screws 33. Plate 32 is also of larger diameter than the barrel 20, so that its outer margin slidably bears against end 35 of housing I9. Barrel 20, retaining plates 3 9 andi 32:, and housing I9 are made of cast alumimun` and 'assembled with suicient tightness to prevent'the leakage of coffee.

Lever I1 is integral with end plate 30 and'is.

the manual means by which the device is set to deliver material to the grinder or to receive material from the hopper. Counterclockwise motion of the handle beyond the relling position is prevented by the bearing of a lug 36 on a limit stop 31. Similarly, clockwise motion beyond the delivery position is prevented by the bearing of lug 36 on a limit stop 38. Stops 31 and 38 are cast in one piece with housing I9 and lug 36 is integral with handle I1.

Adjustment of the device for varying the amount of material measured and delivered is provided by metallic discs 39 and 40, each disc having an individual adjusting screw 4I and 42. The screws turn in threads 43 and 44, respectively, cut in plates 39 and 32, and they are secured in any desired position by lock nuts 45 and 46'.

In accordance with one of the novel features of my invention, the measuring and delivery device isiprovided with a switch 41. This switch is: of the'` plunger type and is mounted on an ear 48' integrally cast on housing I9. The switch is normally biased to a closed position bya spring 62 (Fig. 8) in order to connect motor I8 to a power source (not shown) through al main con-l trol switch 49. However, when the dispensing device is set for refilling, as indicated in Fig. 5,v a cam surface 60 formed onv eccentric portionv 63 of plate 30 depresses switch plunger 5I' andopens the switch, thereby disabling the grinding means by disconnecting the driving motor from its source. Clockwise movement of handle I1- beyond this position (Fig. 4) disengages the cam from the plunger, permits circuit breaker 41 au tomatically to reclose, and starts the motor and grinder.

This feature of the invention produces valuable and important results. When the measuring device is set for refilling the ow of excessive amounts of coffee from the hopper to the bowl of the brewer is prevented in two ways: (1) The portion of barrel 20 diametrically opposite to aperture 21 acts as a. gateand arrests flow from the measuring and delivery device to the grinder; (2) The grinder is turned ofi" by the switch andcannot run. When the operator turns leverv I1, eccentric 83 clears ear 48 and cam 60 releases plunger 5I many degrees preceding the registry of aperture 21 with orice 213. This assures the turning on of motor I8 and the grinder before any coffee is delivered to the grinder, so that the grinder is at operating speed when coffee is released to it. During this clockwise motion, member 2i) continues to block delivery of coffee until knife edge 29 clears the interior surface of casing I9. When the measuring and. delivery device isin the delivering position (Fig. 4), the-portion of barrel 29 diametrically opposite to aperture 21 acts as a barrier to prevent the flow of coffee from the hopper. Therefore, only the measured amount of coffee can be ground. The grinder will continue to run, thus assuring the grinding of the desired predetermined quantity, until lever I'1: is given an approximately 180 counterclockwise turn. Then the measuring and delivery device receives coffee from the hopper stream.. `One operation of lever I1 then causes knife edge 28 to bite off from this stream a measured quantity of coffee, while at the same time turning on the grinder. Thus the cycle is' repeated.

This device eliminates the human equation from the measuring and grinding of coffee. Once discs 39 and 40 have been set for the desired 'f quantity, the sole function of the operator is to turnvlever Il.' Each clockwise turnwill cause the proper measured quantity of ground coffee to be delivered. No manual weighing operations or complex manipulations are required.

The grinder may be of any conventional type. That Adisclosed in my U. 3. Patent 2,187,102, is sued January 16, 1940, is chosen for the purpose of illustration. Reference is made `to that patent for a detailed description of the grinderv 'per se. Briefly however, beans discharged from Ythe measuring and delivery device fall through van opening 53 to the inner or rear face of an inner grinder element -54 and are then forced throughl an opening in that element into the grinding space between that element and the outer grinding element 55. The inner grinding element is xedly mounted on a suitable frame secured to motor I3 while the outer grinder element is rigidly secured to a rotatable shaft 55 yarranged for longitudinal adjustment between inner and outer limits.

Shaft 5'6 extends from the outer element 55 inwardly through the opening in inner element 54. The inner end of the shaft is secured to the drive shaft of motor IB with limited axial freedom of movement to permit longitudinal adjustment of the shaft. The shaft carries, directly behind the inner element 54, a, pair of oppositely disposed blades 5l (of which one is shown) which operate, during rotation, to force the unground material through the opening of element 54 into the grinding space. Shaft 56 extends from the outer grinding element 55 outwardly through a cover member 65.

The clearance between the grinding elements 54 and 55 and therefore the adjustment of the mill for coarse boil, medium pero, fine drip, or other desired grind, is determined by the longitudinal setting of knob 58 in a manner specifically described in the above-mentioned patent. The grinding space is in communication with a delivery oriiice 59.

No claims are herein directed to the grinding device per se. What is claimed as novel is the general combination of a measuring and delivery device and grinder and that combination as it embodies the features whereby one operation assures the measuring and delivery of coffee and the initiation of the grinding operation or whereby one operation places the measuring and delivery device in condition for refilling, turns off the grinding device, and cuts off the delivery of colee to the grinding device. This device is extremely reliable, since it provides: (1) a bar rier between hopper and grinder during delivery of measured coffee to the grinder; (2) a barrier between measuring device and grinder during delivery of unground 4coi-fee to the measuring device; (3) an arrangement for turning off the grinder during refilling of measuring device but for turning it on immediately preceding and during the exhaustion of the measuring device; and (4) an arrangement for keeping the grinder in operative condition until the measuring device is set for refilling.

While I have shown and described what is at present considered to be the preferred embodiment of my invention, it will be obvious to those skilled in the art that various changes and modications may be made therein without departing from the true scope of the invention.

Having described my invention, I claim:

1. In combination, a grinder having an inlet passage and a discharge passage, electric motor 6 means for driving said grinder, a measuring device comprising a rotatable barrel that is `ini-- perforate except for a single opening therein, saidmeasuring device overlying said inlet passage of said grinder, a hopper having a discharge passage'y barrel .opening being substantially coextensivewith the hopper discharge passage when said bai'- rel is in its rst position and substantially coextensive with said inlet passage when in its second position whereby said barrel blocks the ow of material from the hopper when the barrel is rotated from said rst position and blocks the flow from said barrel to said inlet passage when the barrel is rotated from its second position, and means controlled by said manual means for energizing said electric motor and thereby initiating the operation of said grinder as soon as said barrel is removed from said rst position and considerably prior to the communication of the barrel opening with the inlet passage, said last named means including switch means and cam means overlying and engaging said switch means when said barrel is in its first position, said cam means being rotatable with said barrel whereby initial movement of said barrel from its iirst position actuates said switch means to energize said motor.

2. A combination in accordance with claim 1 in which the barrel opening is dened by sharp knife-like edges.

3. A combination in accordance with claim 1 in which stop means engageable with said manual means is provided to prevent rotation of said barrel past its second position and to limit rotation of said barrel between said rst and second positions.

4. In combination, a coiee grinder having an inlet passage and a discharge passage, electric motor means for driving said grinder, a measuring device comprising a rotatable .barrel that is imperforate except for a single opening therein, said measuring device overlying said inlet passage of said grinder, a hopper having a discharge passage overlying said measuring device, a frame for supporting said grinder, said motor means, said measuring device and said hopper, said frame having a base, manual means for rotating said barrel from a rst position whereby its opening is in communication with the hopper discharge passage to a second position whereby its opening is in communication with said inlet passage of said grinder, said barrel when in said first position receiving a predetermined quantity of material from said hopper and when in its second position delivering a predetermined quantity of material to said inlet passage, said barrel opening being substantially coextensive with the hopper discharge passage when said barrel is in its first position and substantially coextensive with said inlet passage when in its second position whereby said barrel blocks the flow of material from the hopper when the barrel is rotated from said rst position and blocks the flow from said barrel to said inlet passage when the barrel is rotated from its second position, and means controlled by said manual means for energizing said electric motor 'ateafsze 7 and therebyinitiat-ing -the'operationof-.said grinder ias soon as ysaid barrel :is .removed r-rom said rst ,position and considerably prior to Athe Acommunication -offthe barrel opening Iwith 'the inlet passage, said last .named :means vinclud-ing :switch means and cam v`means overlying and engaging said y:switch means-when said barrel is in its-first position, said cam means being .rotatable with said barrel whereby initial movement `of ysaid han rel .from vits rst position `aotuates said switch means to energize said motor., `said grinder discharge l-passage being .spacedfabovesaid base and onset forwardly from said motor .means whereby the `bowlofa vacuum `coif ee brewer may loe placed underneath said `grin-der dischargepassage'ito ydi- 15 n 2,461,353

rectiy .receive the material from :saidgrinden RICHARD 1L. :SCHUHMANN REFERENGES CITED .The following references are of Arecord in the file of this patent:

`'UNITED'STATES 'PATENTS Number Nanne Date r424,226 Schenkel et al. -,Mar.`25, 1890 512,837 .McElhiney Jan. 1B, 1894:

14,205,285 Stmpson Nov. .21,.11916 1,942,166 'Gisser Jan...f2, 1934 2.0731100 Keilholz Mar, v16, .1937 l.2,156,075 Alexay Apr...25 1'939 2,187,102 Schumann J an. 16,1940

. 2,339,908 Brewer Jan. 25,1944

Zommer Feb. '8, 1949 

